U.S. patent application number 16/399038 was filed with the patent office on 2019-10-31 for apparatus and method of transmitting and receiving message 3 protocol data unit.
The applicant listed for this patent is Samsung Electronics Co., Ltd.. Invention is credited to Anil AGIWAL, Soenghun KIM.
Application Number | 20190335507 16/399038 |
Document ID | / |
Family ID | 68291405 |
Filed Date | 2019-10-31 |
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United States Patent
Application |
20190335507 |
Kind Code |
A1 |
AGIWAL; Anil ; et
al. |
October 31, 2019 |
APPARATUS AND METHOD OF TRANSMITTING AND RECEIVING MESSAGE 3
PROTOCOL DATA UNIT
Abstract
A communication method and system for converging a fifth
generation (5G) communication system for supporting higher data
rates beyond a fourth generation (4G) system with a technology for
Internet of things (IoT) are provided. The communication method and
system may be applied to intelligent services based on the 5G
communication technology and the IoT-related technology, such as
smart home, smart building, smart city, smart car, connected car,
health care, digital education, smart retail, security and safety
services. A method of a terminal for performing a random access
procedure in a wireless communication system is provided. In
addition, a method by a terminal for system information (SI)
request is provided. A method includes receiving, from a base
station, information on resources for SI request including
information on a start index of at least one random access preamble
for the SI request; receiving, from the base station, at least one
synchronization signal block (SSB); selecting an SSB among the at
least one SSB; determining a preamble for the SI request
corresponding to the selected SSB based on the information on the
start index; and transmitting, to the base station, the determined
preamble based on a physical random access channel (PRACH) occasion
corresponding to the selected SSB.
Inventors: |
AGIWAL; Anil; (Suwon-si,
KR) ; KIM; Soenghun; (Suwon-si, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Samsung Electronics Co., Ltd. |
Suwon-si |
|
KR |
|
|
Family ID: |
68291405 |
Appl. No.: |
16/399038 |
Filed: |
April 30, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62664378 |
Apr 30, 2018 |
|
|
|
62686793 |
Jun 19, 2018 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04W 28/065 20130101;
H04W 84/042 20130101; H04W 28/06 20130101; H04W 88/02 20130101;
H04W 48/18 20130101; H04W 48/12 20130101; H04W 48/16 20130101; H04W
48/14 20130101; H04W 74/0833 20130101; H04W 76/27 20180201; H04W
4/70 20180201 |
International
Class: |
H04W 74/08 20060101
H04W074/08; H04W 76/27 20060101 H04W076/27; H04W 48/16 20060101
H04W048/16; H04W 48/18 20060101 H04W048/18 |
Claims
1. A method by a terminal for system information (SI) request, the
method comprising: receiving, from a base station, information on
resources for SI request including information on a start index of
at least one random access preamble for the SI request; receiving,
from the base station, at least one synchronization signal block
(SSB); selecting an SSB among the at least one SSB; determining a
preamble for the SI request corresponding to the selected SSB based
on the information on the start index; and transmitting, to the
base station, the determined preamble based on a physical random
access channel (PRACH) occasion corresponding to the selected
SSB.
2. The method of claim 1, wherein if the selected SSB is a ith SSB
among SSBs associated with the PRACH occasion, a preamble with an
index increasing the start index by i is determined for the SI
request.
3. The method of claim 1, wherein the information on resources for
the SI request is received in system information block 1 (SIB
1).
4. The method of claim 3, further comprising: receiving, from the
base station, information on a number of SSBs per a PRACH occasion
in the SIB 1.
5. The method of claim 4, further comprising: determining a list of
preambles for the SI request based on the information on the start
index and the information on the number of SSBs per the PRACH
occasion.
6. The method of claim 5, wherein if the number of SSBs per the
PRACH occasion is larger than or equal to 1, the preambles for the
SI request in the list correspond to indices from the start index
to an index increasing the stat index by the number of SSBs per the
PRACH occasion minus 1.
7. The method of claim 4, wherein if the number of SSBs per the
PRACH occasion is less than 1, a preamble with the start index is
determined for the SI request.
8. The method of claim 1, wherein the selecting of the SSB among
the at least one SSB comprises: selecting an SSB above a threshold
among the at least one SSB; and selecting any SSB if none of the at
least one SSB is above the threshold.
9. A terminal in a wireless communication system, the terminal
comprising: a transceiver; a controller coupled with the
transceiver and configured to: control the transceiver to receive,
from a base station, information on resources for system
information (SI) request including information on a start index of
at least one random access preamble for the SI request, control the
transceiver to receive, from the base station, at least one
synchronization signal block (SSB), select an SSB among the at
least one SSB, determine a preamble for the SI request
corresponding to the selected SSB based on the information on the
start index; and control the transceiver to transmit, to the base
station, the determined preamble based on a physical random access
channel (PRACH) occasion corresponding to the selected SSB.
10. The terminal of claim 9, wherein if the selected SSB is a ith
SSB among SSBs associated with the PRACH occasion, the controller
is configured to determine the preamble with an index increasing
the start index by i for the SI request.
11. The terminal of claim 9, wherein the controller is configured
to control the transceiver to receive the information on resources
for the SI request in system information block 1 (SIB1).
12. The terminal of claim 11, wherein the controller is further
configured to control the transceiver to receive from the base
station, information on a number of SSBs per a PRACH occasion in
the SIB 1.
13. The terminal of claim 12, wherein the controller is further
configured to determine a list of preambles for the SI request
based on the information on the start index and the information on
the number of SSBs per the PRACH occasion.
14. The terminal of claim 13, wherein if the number of SSBs per the
PRACH occasion is larger than or equal to 1, the preambles for the
SI request in the list correspond to indices from the start index
to an index increasing the stat index by the number of SSBs per the
PRACH occasion minus 1.
15. The method of claim 12, wherein if the number of SSBs per the
PRACH occasion is less than 1, the controller is configured to
determine the preamble with the start index for the SI request.
16. The method of claim 9, wherein the controller is configured to
select the SSB among the at least one SSB by: selecting an SSB
above a threshold among the at least one SSB, and selecting any SSB
if none of the at least one SSB is above the threshold.
Description
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application is based on and claims priority under 35
U.S.C. .sctn. 119(e) of a U.S. Provisional application Ser. No.
62/664,378, filed on Apr. 30, 2018 in the U.S. Patent and Trademark
Office, and of a U.S. Provisional application Ser. No. 62/686,793,
filed on Jun. 19, 2018, in the U.S. Patent and Trademark Office,
the disclosure of which is incorporated by reference herein its
entirety.
BACKGROUND
1. Field
[0002] The disclosure relates to a system and a method of
transmitting and receiving message 3 protocol data unit (PDU).
2. Description of Related Art
[0003] To meet the demand for wireless data traffic having
increased since deployment of fourth generation (4G) communication
systems, efforts have been made to develop an improved fifth
generation (5G) or pre-5G communication system. Therefore, the 5G
or pre-5G communication system is also called a `beyond 4G network`
or a `post long term evolution (LTE) System`. The 5G wireless
communication system is considered to be implemented not only in
lower frequency bands but also in higher frequency (mmWave) bands,
e.g., 10 GHz to 100 GHz bands, so as to accomplish higher data
rates. To mitigate propagation loss of the radio waves and increase
the transmission (TX) distance, the beamforming, massive
multiple-input multiple-output (MIMO), full dimensional MIMO
(FD-MIMO), array antenna, an analog beam forming, and large scale
antenna techniques are being considered in the design of the 5G
wireless communication system. In addition, in 5G communication
systems, development for system network improvement is under way
based on advanced small cells, cloud radio access networks (RANs),
ultra-dense networks, device-to-device (D2D) communication,
wireless backhaul, moving network, cooperative communication,
coordinated multi-points (CoMP), reception-end interference
cancellation and the like. In the 5G system, hybrid frequency shift
keying (FSK) and quadrature amplitude modulation (QAM), frequency
QAM (FQAM) and sliding window superposition coding (SWSC) as an
advanced coding modulation (ACM), filter bank multi carrier (FBMC),
non-orthogonal multiple access (NOMA), and sparse code multiple
access (SCMA) as an advanced access technology have been
developed.
[0004] The Internet, which is a human centered connectivity network
where humans generate and consume information, is now evolving to
the internet of things (IoT) where distributed entities, such as
things, exchange and process information without human
intervention. The internet of everything (IoE), which is a
combination of the IoT technology and the big data processing
technology through connection with a cloud server, has emerged. As
technology elements, such as "sensing technology", "wired/wireless
communication and network infrastructure", "service interface
technology", and "Security technology" have been demanded for IoT
implementation, a sensor network, a machine-to-machine (M2M)
communication, machine type communication (MTC), and so forth have
been recently researched. Such an IoT environment may provide
intelligent Internet technology services that create a new value to
human life by collecting and analyzing data generated among
connected things. IoT may be applied to a variety of fields
including smart home, smart building, smart city, smart car or
connected cars, smart grid, health care, smart appliances and
advanced medical services through convergence and combination
between existing information technology (IT) and various industrial
applications.
[0005] In line with this, various attempts have been made to apply
5G communication systems to IoT networks. For example,
technologies, such as a sensor network, MTC, and M2M communication
may be implemented by beamforming, MIMO, and array antennas.
Application of a cloud RAN as the above-described big data
processing technology may also be considered to be as an example of
convergence between the 5G technology and the IoT technology.
[0006] In the recent years several broadband wireless technologies
have been developed to meet the growing number of broadband
subscribers and to provide more and better applications and
services. The second generation (2G) wireless communication system
has been developed to provide voice services while ensuring the
mobility of users. Third generation (3G) wireless communication
system supports not only the voice service but also data service.
The 4G wireless communication system has been developed to provide
high-speed data service. However, the 4G wireless communication
system currently suffers from lack of resources to meet the growing
demand for high speed data services. Therefore, the 5G wireless
communication system is being developed to meet the growing demand
of various with diverse requirements, e.g. high speed data
services, support ultra-reliability and low latency
applications.
[0007] In addition, the 5G wireless communication system is
expected to address different use cases having quite different
requirements in terms of data rate, latency, reliability, mobility
etc. However, it is expected that the design of the air-interface
of the 5G wireless communication system would be flexible enough to
serve the user equipments (UEs) having quite different capabilities
depending on the use case and market segment the UE cater service
to the end customer. Example use cases the 5G wireless
communication system wireless system is expected to address is
enhanced mobile broadband (eMBB), massive machine type
communication (m-MTC), ultra-reliable low latency communication
(URLL) etc. The eMBB requirements like tens of Gbps data rate, low
latency, high mobility so on and so forth address the market
segment representing the conventional wireless broadband
subscribers needing internet connectivity everywhere, all the time
and on the go. The m-MTC requirements like very high connection
density, infrequent data transmission, very long battery life, low
mobility address so on and so forth address the market segment
representing the IoT/IoE envisioning connectivity of billions of
devices. The URLL requirements like very low latency, very high
reliability and variable mobility so on and so forth address the
market segment representing the industrial automation application,
vehicle-to-vehicle/vehicle-to-infrastructure communication foreseen
as one of the enabler for autonomous cars.
[0008] In the 5G (also referred as next generation radio or new
radio (NR)) wireless communication system, random access (RA)
procedure is used to achieve uplink time synchronization. RA
procedure is used during initial access, handover, radio resource
control (RRC) connection re-establishment procedure, scheduling
request transmission, secondary cell group (SCG)
addition/modification, beam failure recovery and data or control
information transmission in uplink by non-synchronized UE in RRC
CONNECTED state.
[0009] FIG. 1 shows a contention based RA procedure which comprises
of 4 operations according to the related art. RA preamble (or Msg1)
transmission (operation 110): UE selects one of the available
contention based RA preambles. The contention based RA preambles
can be optionally partitioned into two groups (group A and group
B). If two groups are configured and if the potential Msg3 size (UL
data available for transmission plus MAC header and, where
required, media access control (MAC) control elements (CEs)) is
greater than ra-Msg3SizeGroupA and the pathloss is less than PCMAX
(of the serving cell performing the RA
procedure)--preambleReceivedTargetPower--deltaPreambleMsg3--messagePowerO-
ffsetGroupB, UE select the RA preambles group B. Otherwise UE
select the RA preambles group A. PreambleReceivedTargetPower,
messagePowerOffsetGroupB and ra-Msg3SizeGroupA are configured by
network (e.g. gNB).
[0010] RA response (RAR) or Msg2 (operation 120): gNB transmits the
RAR on physical downlink shared channel (PDSCH) addressed to
RA-radio network temporary identifier (RNTI). RA-RNTI identifies
the time-frequency resource in which RA preamble was detected by
gNB. RAR conveys RA preamble identifier, timing alignment
information, temporary cell-RNTI (C-RNTI) and uplink (UL) grant for
Msg 3.
[0011] Scheduled UL transmission on UL shared channel (SCH) (or
Msg3) (operation 130): It is used to transmit message such as RRC
connection request, RRC connection re-establishment request, RRC
handover confirm, scheduling request, etc. It also includes the UE
identity (i.e. C-RNTI or system architecture evolution
(SAE)-temporary mobile subscriber identity (S-TMSI) or a random
number). Hybrid automatic repeat request (HARQ) is used for this
transmission. This is commonly referred as Msg3.
[0012] Contention resolution message (operation 140): It uses HARQ
and is addressed to C-RNTI (if included in Msg 3) or temporary
C-RNTI (UE identity included in Msg3 is included this case). On
successful decoding of this message, HARQ feedback is only sent by
UE which detects its own UE ID (or C-RNTI).
[0013] In NR the size of Msg3 for RRC connection request is 64 bits
(structure of message: 3 bits; UE identity: 41 bits; Establishment
Cause: 4 bits; MAC header: 2 bytes). The size of Msg3 is 1 byte
more than LTE and hence leads to reduced UL coverage. Similarly the
size of Msg3 for RRC establishment request also requires 64 bits in
NR and should be reduced to 56 bits. The size of Msg3 for RRC
connection resume requires 80 bits and should be reduced to 72
bits.
[0014] A method to reduce the size of Msg3 is needed.
[0015] The above information is presented as background information
only to assist with an understanding of the disclosure. No
determination has been made, and no assertion is made, as to
whether any of the above might be applicable as prior art with
regard to the disclosure.
SUMMARY
[0016] Aspects of the disclosure are to address at least the
above-mentioned problems and/or disadvantages and to provide at
least the advantages described below. Accordingly, an aspect of the
disclosure is to provide a communication method and system for
converging a fifth generation (5G) communication system for
supporting higher data rates beyond a fourth generation (4G)
system.
[0017] Additional aspects will be set forth in part in the
description which follows and, in part, will be apparent from the
description, or may be learned by practice of the presented
embodiments.
[0018] In new radio (NR) the size of Msg3 for radio resource
control (RRC) connection request is 64 bits (structure of message:
3 bits; user equipment (UE) identity: 41 bits; Establishment Cause:
4 bits; media access control (MAC) header: 2 bytes). The size of
Msg3 is 1 byte more than long term evolution (LTE) and hence leads
to reduced uplink (UL) coverage. Similarly the size of Msg3 for RRC
establishment request also requires 64 bits in NR and should be
reduced to 56 bits. The size of Msg3 for RRC connection resume
requires 80 bits and should be reduced to 72 bits.
[0019] In accordance with an aspect of the disclosure, a method of
a terminal for performing a random access procedure in a wireless
communication system is provided. The method includes identifying
whether physical random access channel (PRACH) occasions are
configured for an active uplink (UL) bandwidth part (BWP) of a
serving cell; based on the PRACH occasions not being configured for
the active UL BWP and the serving cell being a special cell
(SpCell), switching an active downlink (DL) BWP of the SpCell; and
performing the random access procedure on the active DL BWP of the
SpCell and the active UL BWP of the serving cell.
[0020] In accordance with an aspect of the disclosure, a terminal
in a wireless communication system is provided. The terminal
includes a transceiver; and at least one processor coupled with the
transceiver and configured to identify whether physical random
access channel (PRACH) occasions are configured for an active
uplink (UL) bandwidth part (BWP) of a serving cell, based on the
PRACH occasions not being configured for the active UL BWP and the
serving cell being a special cell (SpCell), switch an active
downlink (DL) BWP of the SpCell, and perform the random access
procedure on the active DL BWP of the SpCell and the active UL BWP
of the serving cell.
[0021] In accordance with an aspect of the disclosure, a method by
a terminal for transmitting a message 3 (Msg3) in a random access
procedure is provided. The method includes determining that a media
access control (MAC) service data unit (SDU) is associated with a
common control channel (CCCH); identifying a size of the MAC SDU;
determining a logical channel identifier (LCID) field of a MAC
subheader based on the size of the MAC SDU; generating a MAC packet
data unit (PDU) including the MAC subheader and the MAC SDU; and
transmitting, to a base station, the Msg3 associated with the MAC
PDU.
[0022] In accordance with an aspect of the disclosure, a method by
a base station for receiving a message 3 (Msg3) in a random access
procedure is provided. The method includes receiving, from a
terminal, the Msg3 associated with a media access control (MAC)
packet data unit (PDU) including a MAC subheader and a MAC service
data unit (SDU) associated with a common control channel (CCCH);
and identifying a size of the MAC SDU based on a logical channel
identifier (LCID) field of the MAC subheader.
[0023] In accordance with an aspect of the disclosure, a terminal
in a wireless communication system is provided. The terminal
includes a transceiver; and at least one processor coupled with the
transceiver and configured to determine that a media access control
(MAC) service data unit (SDU) is associated with a common control
channel (CCCH), identify a size of the MAC SDU, determine a logical
channel identifier (LCID) field of a MAC subheader based on the
size of the MAC SDU, generate a MAC packet data unit (PDU)
including the MAC subheader and the MAC SDU, and control the
transceiver to transmit, to a base station, a Msg3 associated with
the MAC PDU.
[0024] In accordance with an aspect of the disclosure, a base
station in a wireless communication system is provided. The base
station includes a transceiver; and at least one processor coupled
with the transceiver and configured to control the transceiver to
receive, from a terminal, a Msg3 associated with a media access
control (MAC) packet data unit (PDU) including a MAC subheader and
a MAC service data unit (SDU) associated with a common control
channel (CCCH), and identify a size of the MAC SDU based on a
logical channel identifier (LCID) field of the MAC subheader.
[0025] In accordance with an aspect of the disclosure, a method by
a terminal for system information (SI) request is provided. The
method includes receiving, from a base station, information on
resources for SI request including information on a start index of
at least one random access preamble for the SI request; receiving,
from the base station, at least one synchronization signal block
(SSB); selecting an SSB among the at least one SSB; determining a
preamble for the SI request corresponding to the selected SSB based
on the information on the start index; and transmitting, to the
base station, the determined preamble based on a physical random
access channel (PRACH) occasion corresponding to the selected
SSB.
[0026] In accordance with an aspect of the disclosure, a terminal
in a wireless communication system is provided. The terminal
includes a transceiver; and at least one processor coupled with the
transceiver and configured to control the transceiver to receive,
from a base station, information on resources for system
information (SI) request including information on a start index of
at least one random access preamble for the SI request, control the
transceiver to receive, from the base station, at least one
synchronization signal block (SSB), select an SSB among the at
least one SSB, determine a preamble for the SI request
corresponding to the selected SSB based on the information on the
start index, and control the transceiver to transmit, to the base
station, the determined preamble based on a physical random access
channel (PRACH) occasion corresponding to the selected SSB.
[0027] The embodiments of the disclosure enable reduction of Msg3
size for all types of RRC messages.
[0028] Other aspects, advantages, and salient features of the
disclosure will become apparent to those skilled in the art from
the following detailed description, which, taken in conjunction
with the annexed drawings, discloses various embodiments of the
disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] The above and other aspects, features, and advantages of
certain embodiments of the disclosure will be more apparent from
the following description taken in conjunction with the
accompanying drawings, in which:
[0030] FIG. 1 shows a contention based random access (RA) procedure
which comprises of 4 operation according to the related art;
[0031] FIG. 2 shows the operations according to an embodiment of
the disclosure;
[0032] FIG. 3 illustrates 2 byte R/F/logical channel identifier
(LCID)/L media access control (MAC) subheader according to an
embodiment of the disclosure;
[0033] FIG. 4 illustrates 3 byte R/F/LCID/L MAC subheader according
to an embodiment of the disclosure;
[0034] FIG. 5 illustrates 1 byte R/LCID MAC subheader according to
an embodiment of the disclosure;
[0035] FIG. 6 shows the user equipment (UE) operations according to
an embodiment of the disclosure;
[0036] FIG. 7 shows the next generation node B (gNB) operations
according to an embodiment of the disclosure;
[0037] FIG. 8 shows the UE operations according to an embodiment of
the disclosure;
[0038] FIG. 9 shows the gNB operations according to an embodiment
of the disclosure;
[0039] FIG. 10 shows the UE operations according to an embodiment
of the disclosure;
[0040] FIG. 11 shows the gNB operations according to an embodiment
of the disclosure;
[0041] FIG. 12 shows the operations according to an embodiment of
the disclosure;
[0042] FIG. 13 is an example illustration of mapping preambles in
ra-PreambleIndexList to synchronization signal (SS) blocks (SSBs)
according to an embodiment of the disclosure;
[0043] FIG. 14 illustrates determining the discontinuous reception
(DRX) cycle of UE where remaining minimum system information (RMSI)
is frequency division multiplexed (FDMed) with SSB according to an
embodiment of the disclosure;
[0044] FIG. 15 illustrates determining the DRX cycle of UE where
RMSI is not FDMed with SSB according to an embodiment of the
disclosure;
[0045] FIG. 16 is a block diagram of a terminal according to an
embodiment of the disclosure; and
[0046] FIG. 17 is a block diagram of a base station according to an
embodiment of the disclosure.
[0047] Throughout the drawings, like reference numerals will be
understood to refer to like parts, components, and structures.
DETAILED DESCRIPTION
[0048] The following description with reference to the accompanying
drawings is provided to assist in a comprehensive understanding of
various embodiments of the disclosure as defined by the claims and
their equivalents. It includes various specific details to assist
in that understanding but these are to be regarded as merely
exemplary. Accordingly, those of ordinary skill in the art will
recognize that various changes and modifications of the various
embodiments described herein can be made without departing from the
scope and spirit of the disclosure. In addition, descriptions of
well-known functions and constructions may be omitted for clarity
and conciseness.
[0049] The terms and words used in the following description and
claims are not limited to the bibliographical meanings, but, are
merely used by the inventor to enable a clear and consistent
understanding of the disclosure. Accordingly, it should be apparent
to those skilled in the art that the following description of
various embodiments of the disclosure is provided for illustration
purpose only and not for the purpose of limiting the disclosure as
defined by the appended claims and their equivalents.
[0050] It is to be understood that the singular forms "a," "an,"
and "the" include plural referents unless the context clearly
dictates otherwise. Thus, for example, reference to "a component
surface" includes reference to one or more of such surfaces.
[0051] By the term "substantially" it is meant that the recited
characteristic, parameter, or value need not be achieved exactly,
but that deviations or variations, including for example,
tolerances, measurement error, measurement accuracy limitations and
other factors known to those of skill in the art, may occur in
amounts that do not preclude the effect the characteristic was
intended to provide.
[0052] It is known to those skilled in the art that blocks of a
flowchart (or sequence diagram) and a combination of flowcharts may
be represented and executed by computer program instructions. These
computer program instructions may be loaded on a processor of a
general purpose computer, special purpose computer, or programmable
data processing equipment. When the loaded program instructions are
executed by the processor, they create a means for carrying out
functions described in the flowchart. Because the computer program
instructions may be stored in a computer readable memory that is
usable in a specialized computer or a programmable data processing
equipment, it is also possible to create articles of manufacture
that carry out functions described in the flowchart. Because the
computer program instructions may be loaded on a computer or a
programmable data processing equipment, when executed as processes,
they may carry out operations of functions described in the
flowchart.
[0053] A block of a flowchart may correspond to a module, a
segment, or a code containing one or more executable instructions
implementing one or more logical functions, or may correspond to a
part thereof. In some cases, functions described by blocks may be
executed in an order different from the listed order. For example,
two blocks listed in sequence may be executed at the same time or
executed in reverse order.
[0054] In this description, the words "unit", "module" or the like
may refer to a software component or hardware component, such as,
for example, a field-programmable gate array (FPGA) or an
application-specific integrated circuit (ASIC) capable of carrying
out a function or an operation. However, a "unit", or the like, is
not limited to hardware or software. A unit, or the like, may be
configured so as to reside in an addressable storage medium or to
drive one or more processors. Units, or the like, may refer to
software components, object-oriented software components, class
components, task components, processes, functions, attributes,
procedures, subroutines, program code segments, drivers, firmware,
microcode, circuits, data, databases, data structures, tables,
arrays or variables. A function provided by a component and unit
may be a combination of smaller components and units, and may be
combined with others to compose larger components and units.
Components and units may be configured to drive a device or one or
more processors in a secure multimedia card.
[0055] Prior to the detailed description, terms or definitions
necessary to understand the disclosure are described. However,
these terms should be construed in a non-limiting way.
[0056] The "base station (BS)" is an entity communicating with a
user equipment (UE) and may be referred to as BS, base transceiver
station (BTS), node B (NB), evolved NB (eNB), access point (AP),
fifth generation (5G) NB (5GNB), or next generation NB (gNB).
[0057] The "UE" is an entity communicating with a BS and may be
referred to as UE, device, mobile station (MS), mobile equipment
(ME), or terminal.
[0058] Msg3 Size Reduction
Embodiment 1
[0059] In new radio (NR), a 2 byte or 3 byte media access control
(MAC) subheader is added before each MAC service data unit (SDU).
The MAC subheader comprises of R, F, logical channel ID (LCID) and
L fields. [0060] LCID: The LCID field identifies the logical
channel instance of the corresponding MAC SDU. The LCID field size
is 6 bits; [0061] L: The Length field indicates the length of the
corresponding MAC SDU. The size of the L field is indicated by the
F field; [0062] F: The Format field indicates the size of the
Length field. The size of the F field is 1 bit. The value 0
indicates 8 bits of the Length field. The value 1 indicates 16 bits
of the Length field;
[0063] In one embodiment of the disclosure 1 byte MAC subheader is
used for MAC SDU if the MAC SDU is a common control channel (CCCH)
SDU. Otherwise 2 byte or 3 byte MAC subheader is used for a MAC
SDU. The CCCH SDU can be of multiple sizes (expressed in bits) and
1 byte MAC subheader is used for CCCH SDU irrespective of size of
CCCH SDU. In one embodiment there can be two sizes (size X and size
Y) of CCCH SDU. CCCH SDU of size X and size Y can also be referred
as CCCH and CCCH1 SDU respectively. In the description term CCCH is
commonly used for both CCCH and CCCH1.
[0064] FIG. 2 shows the operations according to an embodiment of
the disclosure.
[0065] 1. Radio resource control (RRC) message is generated and
random access (RA) procedure is triggered by UE at operation
210.
[0066] 2. UE selects RA preamble group based on the information
indicated in the RA configuration (signaled in system information
or in dedicated signaling) and considering the size of RRC message,
type of RRC message and the corresponding MAC subheader at
operation 220. The detail operation of RA preamble group selection
is as follows: [0067] If random access (RA) preambles group B is
configured (i.e. groupBconfigured information element (IE) is
included in RA configuration) and the RRC message is a dedicated
control channel (DCCH) message and size of RRC message plus the
corresponding MAC sub-header (2B or 3B) is greater than
messageSizeGroupA and the pathloss is less than PCMAX (of the
serving cell performing the RA
procedure)--preambleReceivedTargetPower--deltaPreambleMsg3--messagePowerO-
ffsetGroupB: select Random Access Preamble group B;
messageSizeGroupA, preambleReceivedTargetPower, and
messagePowerOffsetGroupB are configured in RA configuration.
deltaPreambleMsg3 is predefined for each physical random access
channel (PRACH) format. [0068] else if Random Access Preambles
group B is configured (i.e. groupBconfigured IE is included in RA
configuration) and the RRC message is CCCH message and size of RRC
message plus the corresponding MAC sub-header (1B) is greater than
messageSizeGroupA: select Random Access Preamble group B; [0069]
else select Random Access Preamble group A.
[0070] 3. UE selects an RA preamble from the selected Random Access
Preamble group and transmits Msg1, i.e. RA preamble at operation
230.
[0071] 4. UE receives a random access response (RAR) corresponding
to its transmitted RA preamble at operation 240. RAR includes UL
grant.
[0072] 5. UE generates MAC PDU by concatenating MAC sub-header and
RRC message (or MAC SDU) at operation 250. If RRC message is CCCH
SDU, 1 byte R/R/LCID MAC subheader is applied. If RRC message is
DCCH SDU, 2 byte or 3 byte R/F/LCID/L MAC subheader is applied
depending on size of DCCH SDU.
[0073] FIG. 3 illustrates 2 byte R/F/LCID/L MAC subheader according
to an embodiment of the disclosure.
[0074] FIG. 4 illustrates 3 byte R/F/LCID/L MAC subheader according
to an embodiment of the disclosure.
[0075] FIG. 5 illustrates 1 byte R/LCID MAC subheader according to
an embodiment of the disclosure.
[0076] A. FIG. 6 shows the UE operations according to an embodiment
of the disclosure.
[0077] Referring to FIG. 6, UE selects one 1 byte MAC subheader at
operation 610.
[0078] Referring to FIG. 5, the 1 byte MAC subheader may include
two 1 bit R field and 6 bits LCID field. The UE sets R fields in
the MAC subheader to zeros at operation 620. In this embodiment,
the UE sets the LCID field in the MAC header based on the size of
CCCH SDU. Specifically, the UE identifies whether the size of CCCH
SDU is M bits at operation 630. The UE sets the LCID field in the
MAC subheader to a pre-defined LCID X, if the size of CCCH SDU is M
bits, at operation 640. Otherwise, the UE identifies whether the
size of CCCH SDU is N bits at operation 650. The UE sets the LCID
field in the MAC subheader to a pre-defined LCID Y, if the size of
CCCH SDU is N bits, at operation 660. The UE sets the LCID field in
the MAC subheader to a pre-defined LCID Z, if the size of CCCH SDU
is other than M and N bits, at operation 670. The values of M and N
are pre-defined in the system. In an example, M can be 48 bits and
N can be 64 bits.
[0079] In an embodiment, a UE determines whether a MAC SDU is
associated with a CCCH or a DCCH. If the MAC SDU corresponds to a
CCCH SDU, the UE identifies the size of the MAC SDU to determine a
LCID field of MAC subheader. The UE generates a MAC PDU including
the MAC subheader and the MAC SDU, and transmits a Msg 3 associated
with the generated MAC PDU to the gNB.
[0080] FIG. 7 shows the gNB operations according to an embodiment
of the disclosure.
[0081] Referring to FIG. 7, gNB reads the LCID in MAC subheader at
operation 710. The gNB identifies whether the LCID is one of the
LCIDs (X, Y, Z) reserved for CCCH SDU at operation 720. Based on
the value of LCID in the MAC subheader of MAC subPDU, the gNB can
know that MAC SDU in MAC subPDU is for CCCH or not. If the MAC SDU
is not for CCCH, the gNB reads the Length field in the MAC
subheader to determine the MAC SDU size at operation 730. If the
MAC subPDU is for CCCH, the gNB can know the length of MAC SDU
based on LCID value. Specifically, the gNB identifies whether the
LCID is equals to X at operation 740. If the LCID is equals to X,
the gNB determines that the CCCH SDU size is M bits at operation
750. If the LCID is not equals to X, the gNB identifies whether the
LCID is equals to Y at operation 760. If the LCID is equals to Y,
the gNB determines that the CCCH SDU size is N bits at operation
770. If the LCID is not equals to X and Y, the gNB determines that
the CCCH SDU size is other than M and N bits at operation 780.
[0082] In an embodiment, the gNB receives a Msg3 associated with a
MAC PDU including a MAC subheader and a MAC SDU from a UE. The LCID
in MAC subheader may indicate that the MAC SDU is associated with a
CCCH. If the received MAC SDU is a CCCH SDU, the gNB identifies the
size of the MAC SDU based on a LCID field of the MAC subheader.
[0083] B. FIG. 8 shows the UE operations according to an embodiment
of the disclosure.
[0084] Referring to FIG. 8, UE includes one 1 byte MAC subheader at
operation 810. As shown in FIG. 5, the 1 byte MAC subheader may
include two 1 bit R field and 6 bits LCID field. The UE sets R
fields in the MAC subheader to zeros at operation 820. In this
embodiment, the UE sets the LCID field in the MAC header based on
the size of CCCH SDU. Specifically, the UE identifies whether the
size of CCCH SDU is M bits at operation 830. The UE sets the LCID
field in the MAC subheader to a pre-defined LCID X, if the size of
CCCH SDU is M bits, at operation 840. The UE sets the LCID field in
the MAC subheader to a pre-defined LCID Y, if the size of CCCH SDU
is N bits, at operation 850. The values of M and N are pre-defined
in the system. In an example, M can be 48 bits and N can be 64
bits. CCCH SDU of size M bits and size N bits can also be referred
as CCCH SDU and CCCH1 SDU respectively.
[0085] FIG. 9 shows the gNB operations according to another
embodiment of the disclosure.
[0086] Referring to FIG. 9, gNB reads the LCID in MAC subheader at
operation 910. The gNB identifies whether the LCID is one of the
LCIDs (X, Y) reserved for CCCH SDU at operation 920. Based on the
value of LCID in the MAC subheader of MAC subPDU, the gNB can know
that MAC SDU in MAC subPDU is for CCCH or not. If the MAC SDU is
not for CCCH LCID corresponds to dedicated control or traffic
channel, the MAC subheader is a 2B or 3B MAC subheader and the gNB
reads the Length field in the MAC subheader to determine the MAC
SDU size at operation 930. If the MAC subPDU is for CCCH the gNB
can know the length of MAC SDU based on LCID value. Specifically,
the gNB identifies whether the LCID is equals to X at operation
940. If the LCID is equals to X, the gNB determines that the CCCH
SDU size is M bits at operation 950. If the LCID is not equals to
X, i.e., the LCID is equals to Y, the gNB determines that the CCCH
SDU size is N bits at operation 960.
[0087] C. FIG. 8, UE sets the LCID field in the MAC subheader to a
pre-defined LCID X, if the size of CCCH SDU is M bits, at operation
840. UE sets the LCID field in the MAC subheader to a pre-defined
LCID Y, if the size of CCCH SDU is other than M bits, at operation
850. The value of M is pre-defined in the system. In an example, M
can be 48 bits. Based on the value of LCID in MAC subheader of MAC
subPDU, gNB can know that MAC SDU in MAC subPDU is for CCCH or not.
If the MAC subPDU is for CCCH it can know the length of MAC SDU
based on LCID value.
[0088] D. FIG. 10 shows the UE operations according to an
embodiment of the disclosure.
[0089] Referring to FIG. 10, UE includes one 1 byte MAC subheader
at operation 1010. As shown in FIG. 5, the 1 byte MAC subheader may
include two 1 bit R field and 6 bits LCID field. The UE sets first
R, i.e. R1 field in the MAC subheader to zeros at operation 1020.
In this embodiment, the UE sets the LCID field in the MAC header
based on the size of CCCH SDU. The UE sets the LCID field in the
MAC subheader to a pre-defined LCID X, if the size of CCCH SDU is M
or N bits. Specifically, the UE identifies whether the size of CCCH
SDU is M bits at operation 1030. If the size of CCCH SDU is M bits,
the UE sets the LCID field in the MAC subheader to a pre-defined
LCID X at operation 1040, and the UE sets second R field to 1 at
operation 1050. The UE identifies whether the size of CCCH SDU is N
bits at operation 1060. If the size of CCCH SDU is N bits, the UE
sets the LCID field in the MAC subheader to a pre-defined LCID X at
operation 1070, and the UE sets second R field to 0 at operation
1080. The UE sets the LCID field in the MAC subheader to a
pre-defined LCID Y, if the size of CCCH SDU is neither M nor N
bits, at operation 1090. If the size of CCCH SDU is neither M nor N
bits, second R field is set to zero at operation 1100. The values
of M and N are pre-defined in the system. In an example, M can be
48 bits and N can be 64 bits.
[0090] FIG. 11 shows the gNB operations according to an embodiment
of the disclosure.
[0091] Referring to FIG. 11, gNB reads the LCID in MAC subheader at
operation 1110. The gNB identifies whether the LCID is one of the
LCIDs (X, Y) reserved for CCCH SDU at operation 1120. Based on the
value of LCID in the MAC subheader of MAC subPDU, the gNB can know
that MAC SDU in MAC subPDU is for CCCH or not. If the MAC SDU is
not for CCCH, and LCID corresponds to dedicated control or traffic
channel, the MAC subheader is a 2B or 3B MAC subheader and the gNB
reads the Length field in MAC subheader to determine the MAC SDU
size at operation 1130. If the MAC SDU is for CCCH, the gNB
identifies whether the LCID is equals to X at operation 1140. If
the LCID is not equals to X, the gNB determines that CCCH SDU size
is other than M and N bits at operation 1150. If the LCID is equals
to X, the gNB identifies whether R2 field in MAC subheader is set
to 1 at operation 1160. If the R2 field in the MAC subheader is set
to 1, the gNB determines that CCCH SDU size is M bits at operation
1170. If the R2 filed in the MAC subheader is not set to 1, the gNB
determines that CCCH SDU size is N bits at operation 1180.
[0092] 6. The UE transmits the generated MAC PDU to the gNB at
operation 260.
[0093] In an embodiment, UE (i.e. transmitter) determines whether
the RRC message to be transmitted is a CCCH message or not. If the
RRC message to be transmitted is a CCCH message, the UE includes a
MAC subPDU in MAC PDU wherein the MAC subPDU comprises of 1 byte
R/R/LCID MAC subheader and CCCH message. If the RRC message to be
transmitted is a DCCH message, the UE includes a MAC subPDU in MAC
PDU wherein the MAC subPDU comprises of 2 byte or 3 byte R/F/LCID/L
MAC subheader and DCCH message.
[0094] In an embodiment, gNB (i.e. receiver) determines whether the
MAC SDU is a CCCH SDU or not in the received MAC subPDU. If the MAC
SDU is a CCCH SDU, MAC subheader in MAC subPDU is a 1 byte R/R/LCID
MAC subheader. If the MAC SDU is not a CCCH SDU, MAC subheader in
MAC subPDU is a 2 byte or 3 byte R/F/LCID/L MAC subheader.
[0095] In an embodiment of the disclosure if size of CCCH SDU is M
bits, UE selects one byte MAC subheader for CCCH and sets LCID in
MAC subheader to a pre-defined LCID X. If size of CCCH SDU is other
than M bits, UE sets LCID in MAC subheader to a pre-defined LCID Y.
If CCCH SDU is other than M bits, UE selects 1 byte MAC subheader
if UL grant size is N bits. If CCCH SDU is other than M bits, UE
selects 2 byte MAC subheader if UL grant size is greater than N
bits. M and N are pre-defined.
Embodiment 2
[0096] In NR, a 2 byte or 3 byte MAC subheader is added before each
MAC SDU. The MAC subheader comprise of R, F, LCID and L fields.
[0097] LCID: The Logical Channel ID field identifies the logical
channel instance of the corresponding MAC SDU. The LCID field size
is 6 bits; [0098] L: The Length field indicates the length of the
corresponding MAC SDU. The size of the L field is indicated by the
F field; [0099] R: Reserved bit, set to zero.
[0100] In one embodiment of the disclosure 1 byte MAC subheader is
used for MAC SDU if the MAC SDU is a CCCH SDU. Otherwise 2 byte or
3 byte MAC subheader is used for a MAC SDU. The CCCH SDU can be of
multiple sizes (expressed in bits) and 1 byte MAC subheader is used
for CCCH SDU irrespective of size of CCCH SDU. In one embodiment
there can be two sizes (size X and size Y) of CCCH SDU. CCCH SDU of
size X and size Y can also be referred as CCCH and CCCH1 SDU
respectively. In the description term CCCH is commonly used for
both CCCH and CCCH1.
[0101] FIG. 12 shows the operations according to Embodiment 2 of
the disclosure.
[0102] 1. RA procedure is triggered by UE at operation 1210.
[0103] 2. UE selects RA preamble group based on the information
indicated in the RA configuration (signaled in system information
or in dedicated signaling) and considering the size of Msg3, type
of MAC SDU in Msg3 at operation 1220. The detail operation of RA
preamble group selection is as follows: [0104] If RA preambles
group B is configured (i.e. groupBconfigured IE is included in RA
configuration) and the Msg3 does not include CCCH SDU and size of
Msg3 (MAC SDU plus the corresponding MAC sub-header (2B or 3B)) is
greater than messageSizeGroupA and the pathloss is less than PCMAX
(of the serving cell performing the RA
Procedure)--preambleReceivedTargetPower--deltaPreambleMsg3--messagePowerO-
ffsetGroupB: select Random Access Preamble group B; [0105] else if
RA preambles group B is configured (i.e. groupBconfigured IE is
included in RA configuration) and the Msg3 includes CCCH SDU and
size of Msg3 (MAC SDU plus the corresponding MAC sub-header (1B))
is greater than messageSizeGroupA: select Random Access Preamble
group B; [0106] else select RA preamble group A
[0107] 3. UE selects an RA preamble from the selected RA preamble
group and transmits Msg1, i.e. RA preamble at operation 1230.
[0108] 4. UE receives an RAR corresponding to its transmitted RA
preamble at operation 1240. RAR includes UL grant.
[0109] 5. UE generates MAC PDU by concatenating MAC sub-header and
MAC SDU at operation 1250. If MAC SDU is CCCH SDU, 1B R/R/LCID MAC
subheader (FIG. 5) may be applied. If MAC SDU is not CCCH SDU, 2B
or 3B R/F/LCID/L MAC subheader (FIGS. 3, 4) may be applied.
[0110] A. In an embodiment of the disclosure (as shown in FIG. 6),
UE sets the LCID in MAC subheader to a pre-defined LCID X, if the
size of CCCH SDU is M bits. UE sets the LCID in MAC subheader to a
pre-defined LCID Y, if the size of CCCH SDU is N bits. UE sets the
LCID in MAC subheader to a pre-defined LCID Z, if the size of CCCH
SDU is other than M and N bits. The values of M and N are
pre-defined in the system. In an example, M can be 48 bits and N
can be 64 bits. Based on the value of LCID in MAC subheader of MAC
subPDU, gNB can know that MAC SDU in MAC subPDU is for CCCH or not.
If the MAC subPDU is for CCCH the gNB can know the length of MAC
SDU based on LCID value. In an embodiment if the size of CCCH SDU
is other than M and N bits and if there can be several CCCH SDU
sizes other than M and N bits, UE can add 2 byte MAC subheader
which includes the length field. GNB operations in an embodiment
are shown in FIG. 7.
[0111] In an embodiment of the disclosure (as shown in FIG. 8), UE
sets the LCID in MAC subheader to a pre-defined LCID X, if the size
of CCCH SDU is M bits. UE sets the LCID in MAC subheader to a
pre-defined LCID Y, if the size of CCCH SDU is N bits. The values
of M and N are pre-defined in the system. In an example, M can be
48 bits and N can be 64 bits. Based on the value of LCID in MAC
subheader of MAC subPDU, gNB can know that MAC SDU in MAC subPDU is
for CCCH or not. If the MAC subPDU is for CCCH, the gNB can know
the length of MAC SDU based on LCID value. GNB operations in an
embodiment are shown in FIG. 9.
[0112] C. In an embodiment of the disclosure (as shown in FIG. 8),
UE sets the LCID in MAC subheader to a pre-defined LCID X, if the
size of CCCH SDU is M bits. UE sets the LCID in MAC subheader to a
pre-defined LCID Y, if the size of CCCH SDU is other than M bits.
The value of M is pre-defined in the system. In an example, M can
be 48 bits. Based on the value of LCID in MAC subheader of MAC
subPDU, gNB can know that MAC SDU in MAC subPDU is for CCCH or not.
If the MAC subPDU is for CCCH, the gNB can know the length of MAC
SDU based on LCID value. GNB operations in an embodiment are shown
in FIG. 9.
[0113] D. In an embodiment of the disclosure (as shown in FIG. 10),
UE sets the LCID in MAC subheader to a pre-defined LCID X, if the
size of CCCH SDU is M or N bits. If the size of CCCH SDU is M bits,
second R field is set to 1. If the size of CCCH SDU is N bits,
second R field is set to 0. UE sets the LCID in MAC subheader to a
pre-defined LCID Y, if the size of CCCH SDU is neither M nor N
bits. If the size of CCCH SDU is neither M nor N bits, second R
field is set to zero. The values of M and N are pre-defined in the
system. In an example, M can be 48 bits and N can be 64 bits. GNB
operations in an embodiment are shown in Figure FIG. 10.
[0114] 6. The UE transmits the generated MAC PDU to the gNB at
operation 1260.
[0115] In an embodiment, UE (i.e. transmitter) determines whether
the MAC SDU to be transmitted is a CCCH SDU or not. If the MAC SDU
to be transmitted is a CCCH SDU, the UE includes a MAC subPDU in
MAC PDU wherein the MAC subPDU comprises of 1 byte R/R/LCID MAC
subheader and MAC SDU. If the MAC SDU to be transmitted is not a
CCCH SDU, the UE includes a MAC subPDU in MAC PDU wherein the MAC
subPDU comprises of 2 byte or 3 byte R/F/LCID/L MAC subheader and
MAC SDU.
[0116] In an embodiment, gNB (i.e. receiver) determines whether the
MAC SDU is a CCCH SDU or not in the received MAC subPDU. If the MAC
SDU is a CCCH SDU, MAC subheader in MAC subPDU is a 1 byte R/R/LCID
MAC subheader. If the MAC SDU is not a CCCH SDU, MAC subheader in
MAC subPDU is a 2 byte or 3 byte R/F/LCID/L MAC subheader.
[0117] In an embodiment of the disclosure if size of CCCH SDU is M
bits, UE selects one byte MAC subheader for CCCH and sets LCID in
MAC subheader to a pre-defined LCID X. If size of CCCH SDU is other
than M bits, UE sets LCID in MAC subheader to a pre-defined LCID Y.
If CCCH SDU is other than M bits, UE selects 1 byte MAC subheader
if UL grant size is N bits. If CCCH SDU is other than M bits, UE
selects 2 byte MAC subheader if UL grant size is greater than N
bits. M and N are pre-defined.
[0118] Signaling RA Resources for System Information (SI)
Request
[0119] In NR there is an association between synchronization signal
(SS) blocks (SSBs) and PRACH preambles/PRACH occasions. This
enables gNB to identify the TX beam for transmitting Msg2. This
also enables gNB to receive Msg 1 using specific RX beam(s) in
specific PRACH occasion. So, the RA resource for each SI request
needs to be signaled per SSB.
[0120] si-Request-Resources can be signaled in SIB1 wherein
si-Request-Resources is a list of SI-Request-Resources.
si-Request-Resources indicates RA resources for a SI request. Each
entry in the list si-Request-Resources contains RA resources
corresponding to a SI request. If there is only one entry in the
list, the RA resources in this entry are used for all SI messages
which are provided on demand. Otherwise RA resources in 1st entry
in the list corresponds to first on demand SI message in
schedulingInfoList, RA resources in 2nd entry in the list
corresponds to second on demand SI message in schedulingInfoList
and so on.
[0121] There are several options to signal RA resources for a SI
request, i.e. to define SI-Request-Resources.
Approach 1:
[0122] For each SI request, ra-PreambleIndex can be signaled for
each SSB explicitly as shown below. See Table 1 below. Network
(i.e. gNB) signals the same in system information, i.e. SIB1;
ra-PreambleIndexList is signaled for each SI request wherein the
ra-PreambleIndexList includes SSB index and ra-PreambleIndex.
ra-ssb-OccasionMaskIndex is also signaled for each SI request;
ra-ssb-OccasionMaskIndex is the index to a pre-defined PRACH mask
index table wherein each entry in the table indicates the random
access channel (RACH) occasions(s) to be used. Note that
ra-ssb-OccasionMaskIndex is not signaled for each SSB. The signaled
value of ra-ssb-OccasionMaskIndex is applicable to all SSBs. UE
selects a suitable SSB (above a threshold configured by network in
system information). UE then selects a preamble corresponding to
this SSB from SI-Request-Resources corresponding to SI message
which UE wants to request. UE also selects a RACH occasion
(indicated by ra-ssb-OccasionMaskIndex or rach occasion index)
corresponding to this SSB from SI-Request-Resources corresponding
to SI message which UE wants to request. If
ra-ssb-OccasionMaskIndex is not signaled, UE can select next
available RACH occasion from the RACH occasions corresponding to
this SSB.
[0123] This approach may lead to significant overhead (up to
4+(6+6)*64=772 bits for one SI request configuration, where
ra-ssb-OccasionMaskIndex is 4 bits, ra-PreambleIndex is 6 bits,
SSB-Index is 6 bits and number of SSBs is 64) because of large
number of SSBs (up to 64).
TABLE-US-00001 TABLE 1 Parameters (ASN.1) for RA Resources for SI
Request si-Request-Config SI-Request-Config OPTIONAL, --
Configuration for Msg1 based SI Request SI-Request-Config ::=
SEQUENCE { --List of SI Request Resources si-Request-Resources ::=
SEQUENCE (SIZE (1..maxSI-Message)) OF SI-Request-Resources } } --
Resources for a SI Request SI-Request-Resources::= SEQUENCE {
ra-PreambleIndexList SEQUENCE (SIZE (1..maxSSBs)) OF
RAPreambleIndex, ra-ssb-OccasionMaskIndex INTEGER (0..15) }
RAPreambleIndex::= SEQUENCE { ssb SSB-Index, ra-PreambleIndex
INTEGER (0..63)
Approach 2:
[0124] Alternate approach to embodiment 1 is to signal a list
(ra-PreambleIndexList) of ra-PreambleIndexes for each SI request
wherein the SSB Index associated with a ra-PreambleIndex is not
signaled; ra-PreambleIndexList is included in SI-Request-Resources.
See Table 2 below. Network (i.e. gNB) signals the same in system
information, i.e. SIB1. If multiple SSBs are mapped to same PRACH
occasion, different dedicated PRACH preambles are needed to
distinguish these SSBs. If only one SSB is mapped to one PRACH
occasion or to multiple PRACH occasions, only one dedicated
preamble is needed. So, if the number of SSBs per PRACH occasion is
less than or equal to 1, the size of this list is 1. If the number
of SSBs per PRACH occasion is less than one, preamble with preamble
index=ra-PreambleStartIndex is used for SI request and corresponds
to all SSBs. If the number of SSBs per PRACH occasion is larger
than or equal to 1, the size of this list is equal to number of
SSBs per PRACH occasion and the `ith` preamble in this list
(ra-PreambleIndexList) corresponds to ith SSB among the SSBs
associated with a PRACH Occasion. The maximum overhead for one SI
request configuration is 4+6*16=100 bits where
ra-ssb-OccasionMaskIndex is 4 bits, RAPreambleIndex is 6 bits,
maximum number of SSBs per PRACH Occasion is 16.
TABLE-US-00002 TABLE 2 Parameters (ASN.1) for RA Resources for SI
Request si-Request-Config SI-Request-Config OPTIONAL, --
Configuration for Msg1 based SI Request SI-Request-Config ::=
SEQUENCE { --List of SI Request Resources si-Request-Resources ::=
SEQUENCE (SIZE (1..maxSI-Message)) OF SI-Request-Resources } } --
Resources for a SI Request SI-Request-Resources::= SEQUENCE {
ra-PreambleIndexList SEQUENCE (SIZE (1..16)) OF INTEGER (0..63),
ra-ssb-OccasionMaskIndex INTEGER (0..15) }
[0125] FIG. 13 is an example illustration of mapping preambles in
ra-PreambleIndexList to SSBs.
[0126] In the example 4 SSBs are mapped per PRACH occasion and
there are 16 SSBs. In this case ra-PreambleIndexList includes four
preamble indexes (e.g. P1, P2, P3 and P4). The `ith` preamble in
this list corresponds to ith SSB among the SSBs associated with a
PRACH Occasion.
[0127] 1. SSB0 to SSB 3 are mapped to RO#1. So P1 corresponds to
first SSB (i.e. SSB 0) associated with RO#1, P2 corresponds to
second SSB (i.e. SSB1) associated with RO#1, P3 corresponds to
third SSB (i.e. SSB2) associated with RO#1, and P4 corresponds to
fourth SSB (i.e. SSB3) associated with RO#1.
[0128] 2. SSB4 to SSB 7 are mapped to RO#2. So P1 corresponds to
first SSB (i.e. SSB 4) associated with RO#2, P2 corresponds to
second SSB (i.e. SSB5) associated with RO#2, P3 corresponds to
third SSB (i.e. SSB6) associated with RO#2, and P4 corresponds to
fourth SSB (i.e. SSB7) associated with RO#2.
[0129] 3. SSB8 to SSB 11 are mapped to RO#3. So P1 corresponds to
first SSB (i.e. SSB 8) associated with RO#3, P2 corresponds to
second SSB (i.e. SSB9) associated with RO#3, P3 corresponds to
third SSB (i.e. SSB10) associated with RO#3, and P4 corresponds to
fourth SSB (i.e. SSB11) associated with RO#3.
[0130] 4. SSB12 to SSB 15 are mapped to RO#4. So P1 corresponds to
first SSB (i.e. SSB 12) associated with RO#4, P2 corresponds to
second SSB (i.e. SSB13) associated with RO#4, P3 corresponds to
third SSB (i.e. SSB14) associated with RO#4, and P4 corresponds to
fourth SSB (i.e. SSB15) associated with RO#4.
[0131] UE selects a suitable SSB (above a threshold configured by
network in system information). UE then selects a preamble
corresponding to this SSB from SI-Request-Resources corresponding
to SI message which UE wants to request. UE also selects a RACH
occasion (indicated by ra-ssb-OccasionMaskIndex or rach occasion
index) corresponding to this SSB from SI-Request-Resources
corresponding to SI message which UE wants to request. UE then
transmits Msg1 using selected preamble and RACH occasion.
[0132] Embodiment 2 in an embodiment, instead of signaling a list
of ra-PreambleIndexes as explained in embodiment 1,
ra-PreambleStartIndex indicating a start index of at least one RA
preamble for each SI request can be signaled as shown below.
ra-PreambleStartIndex is included in SI-Request-Resources. See
Table 3 below. Network (i.e. gNB) signals the same in system
information, i.e. SIB1. UE can determine the list of
ra-PreambleIndexes based on ra-PreambleStartIndex and number of
SSBs per RACH Occasion. The number of SSBs per RACH Occasion is
also signaled in system information, i.e. SIB1.
[0133] Mapping of preambles to SSBs based on ra-PreambleStartIndex
(option 1): If the number of SSBs per PRACH occasion is less than
one, the preamble with preamble index=ra-PreambleStartIndex is used
for SI request. This preamble is used for any SSB selected by UE.
If the number of SSBs per PRACH occasion is larger than or equal to
1, PRACH preambles from ra-PreambleStartIndex to
`ra-PreambleStartIndex+number of SSBs per RACH Occasion-1` are used
for this SI request. The `ith` preamble in this list corresponds to
ith SSB among the SSBs associated with a RACH Occasion. In other
words, if N SSBs are associated with a RACH occasion, where
N>=1, for the i.sup.th SSB (i=0, . . . , N-1) mapped to a RACH
occasion, preamble with preamble index=ra-PreambleStartIndex+i is
used for SI request; For N<1, the preamble with preamble
index=ra-PreambleStartIndex is used for this SI request.
[0134] Referring to FIG. 13, 4 SSBs are mapped per PRACH occasion
and there are 16 SSBs. Network signals ra-PreambleStartIndex for SI
request in SI-Request-Resources. PRACH preambles from
ra-PreambleStartIndex to `ra-PreambleStartIndex+3` are used for
this SI request.
[0135] 1. SSB0 to SSB 3 are mapped to RO#1. So P1 (indicated by
ra-PreambleStartIndex) corresponds to SSB0, P2 (indicated by
ra-PreambleStartIndex+1) corresponds to SSB1, P3 (indicated by
ra-PreambleStartIndex+2) corresponds to SSB2, and P4 (indicated by
ra-PreambleStartIndex+3) corresponds to SSB3.
[0136] 2. SSB4 to SSB 7 are mapped to RO#2. So P1 (indicated by
ra-PreambleStartIndex) corresponds to SSB4, P2 (indicated by
ra-PreambleStartIndex+1) corresponds to SSB5, P3 (indicated by
ra-PreambleStartIndex+2) corresponds to SSB6, and P4 (indicated by
ra-PreambleStartIndex+3) corresponds to SSB7.
[0137] 3. SSB8 to SSB 11 are mapped to RO#3. So P1 (indicated by
ra-PreambleStartIndex) corresponds to SSB8, P2 (indicated by
ra-PreambleStartIndex+1) corresponds to SSB9, P3 (indicated by
ra-PreambleStartIndex+2) corresponds to SSB10, and P4 (indicated by
ra-PreambleStartIndex+3) corresponds to SSB11.
[0138] 4. SSB12 to SSB 15 are mapped to RO#3. So P1 (indicated by
ra-PreambleStartIndex) corresponds to SSB12, P2 (indicated by
ra-PreambleStartIndex+1) corresponds to SSB13, P3 (indicated by
ra-PreambleStartIndex+2) corresponds to SSB14, and P4 (indicated by
ra-PreambleStartIndex+3) corresponds to SSB15.
TABLE-US-00003 TABLE 3 Parameters (ASN.1) for RA Resources for SI
Request si-Request-Config SI-Request-Config OPTIONAL, --
Configuration for Msg1 based SI Request SI-Request-Config ::=
SEQUENCE { --List of SI Request Resources si-Request-Resources ::=
SEQUENCE (SIZE (1..maxSI-Message)) OF SI-Request-Resources } }
SI-Request-Resources::= SEQUENCE { ra-PreambleStartIndex INTEGER
(0..63), ra-ssb-OccasionMaskIndex INTEGER (0..15) }
[0139] Mapping of preambles to SSBs based on ra-PreambleStartIndex
(option 2): If N SSBs are associated with a RACH occasion, where
N>=1, for the i.sup.th SSB (i=0, . . . , N-1) mapped to a RACH
occasion, preamble with preamble
index=ra-PreambleStartIndex+i*(64/N) is used for SI request; For
N<1, the preamble with preamble index=ra-PreambleStartIndex is
used for this SI request. In the example of FIG. 13, 4 SSBs are
mapped per PRACH occasion and there are 16 SSBs. Network signals
ra-PreambleStartIndex for SI request in SI-Request-Resources.
[0140] SSB0 to SSB 3 are mapped to RO#1. So P1 (indicated by
ra-PreambleStartIndex+0*(64/4)) corresponds to SSB0, P2 (indicated
by ra-PreambleStartIndex+(64/4)) corresponds to SSB1, P3 (indicated
by ra-PreambleStartIndex+2*(64/4)) corresponds to SSB2, and P4
(indicated by ra-PreambleStartIndex+3*(64/4)) corresponds to
SSB3.
[0141] SSB4 to SSB 7 are mapped to RO#2. So P1 (indicated by
ra-PreambleStartIndex+0*(64/4)) corresponds to SSB4, P2 (indicated
by ra-PreambleStartIndex+1*(64/4)) corresponds to SSB5, P3
(indicated by ra-PreambleStartIndex+2*(64/4)) corresponds to SSB6,
and P4 (indicated by ra-PreambleStartIndex+3*(64/4)) corresponds to
SSB7.
[0142] SSB8 to SSB 11 are mapped to RO#3. So P1 (indicated by
ra-PreambleStartIndex+0*(64/4)) corresponds to SSB8, P2 (indicated
by ra-PreambleStartIndex+1*(64/4)) corresponds to SSB9, P3
(indicated by ra-PreambleStartIndex+2*(64/4)) corresponds to SSB10,
and P4 (indicated by ra-PreambleStartIndex+3*(64/4)) corresponds to
SSB11.
[0143] SSB12 to SSB 15 are mapped to RO#3. So P1 (indicated by
ra-PreambleStartIndex+0*(64/4)) corresponds to SSB12, P2 (indicated
by ra-PreambleStartIndex+1*(64/4)) corresponds to SSB13, P3
(indicated by ra-PreambleStartIndex+2*(64/4)) corresponds to SSB14,
and P4 (indicated by ra-PreambleStartIndex+3*(64/4)) corresponds to
SSB15.
[0144] UE receives at least one SSB from gNB, and UE selects a
suitable SSB (above a threshold configured by network in system
information) among the at least one SSB. If none of SSB is
suitable, UE may select any SSB. UE then selects a preamble
corresponding to this SSB from SI-Request-Resources corresponding
to SI message which UE wants to request. UE also selects a RACH
occasion (indicated by ra-ssb-OccasionMaskIndex or rach occasion
index) corresponding to this SSB from SI-Request-Resources
corresponding to SI message which UE wants to request. If
ra-ssb-OccasionMaskIndex is not signaled, UE can select next
available RACH occasion from the RACH occasions corresponding to
selected SSB. UE then transmits Msg1 using selected preamble and
RACH occasion.
Embodiment 3
[0145] In embodiment 3, instead of signaling ra-PreambleStartIndex
for each SI request as explained in embodiment 2,
ra-PreambleStartIndex can be indicated for on demand SI. UE can
determine the list of ra-PreambleIndexes based on
ra-PreambleStartIndex, number of SSBs per RACH Occasion and
configuration type.
[0146] If configuration type is common, this means there is a
common configuration for all on Demand SI messages. This can be
indicated by signaling configuration type set to `common`.
Alternately, if dedicatedConfig is not included then configuration
type is common. In this case Msg1 (i.e. SI request) transmitted by
UE does not indicate request for a specific SI message and upon
reception of Msg1 network transmits all On-Demand SI messages. In
this case if the number of SSBs per PRACH occasion is larger than
or equal to 1, PRACH preambles from ra-PreambleStartIndex to
`ra-PreambleStartIndex+number of SSBs per RACH Occasion-1` are used
for SI request. The `ith` preamble in this list corresponds to ith
SSB among the SSBs associated with a RACH Occasion. In the example
of FIG. 13, 4 SSBs are mapped per PRACH occasion and there are 16
SSBs. Network signals ra-PreambleStartIndex for SI request in
SI-Request-Resources. PRACH preambles from ra-PreambleStartIndex to
`ra-PreambleStartIndex+3` are used for this SI request. If the
number of SSBs per PRACH occasion is less than 1, preamble
index=ra-PreambleStartIndex is used for SI request for any SSB.
[0147] If configuration type is dedicated, this means there is a
dedicated configuration for each on Demand SI message. This can be
indicated by signaling configuration type set to `dedicated.`
Alternately, if dedicatedConfig is included then configuration type
is dedicated. In this case, if the number of SSBs per PRACH
occasion is larger than or equal to 1
[0148] 1. The list of PRACH preambles from ra-PreambleStartIndex to
`ra-PreambleStartIndex+number of SSBs per RACH Occasion-1` are used
for first On-Demand SI message in schedulingInfoList. Mapping
between this list of preambles and SSBs is determined as explained
in embodiments 2 and 3. SchedulingInfoList is a list of SI message
and indicates which SI message is On demand or broadcasted.
[0149] 2. The list of PRACH preambles from
`ra-PreambleStartIndex+number of SSBs per RACH Occasion` to
`ra-PreambleStartIndex+2*number of SSBs per RACH Occasion-1` are
used for second On-Demand SI message in schedulingInfoList. Mapping
between this list of preambles and SSBs is determined as explained
in embodiments 2 and 3. schedulingInfoList is a list of SI message
and indicates which SI message is On demand or broadcasted.
[0150] 3. The list of PRACH preambles from
`ra-PreambleStartIndex+2*number of SSBs per RACH Occasion` to
`ra-PreambleStartIndex+3*number of SSBs per RACH Occasion-1` are
used for third On-Demand SI message in schedulingInfoList. Mapping
between this list of preambles and SSBs is determined as explained
in embodiments 2 and 3. schedulingInfoList is a list of SI message
and indicates which SI message is On demand or broadcasted.
[0151] 4. The list of PRACH preambles from
`ra-PreambleStartIndex+(n-1)*number of SSBs per RACH Occasion` to
`ra-PreambleStartIndex+n*number of SSBs per RACH Occasion-1` are
used for nth On-Demand SI message in schedulingInfoList. Mapping
between this list of preambles and SSBs is determined as explained
in embodiments 2 and 3. schedulingInfoList is a list of SI message
and indicates which SI message is On demand or broadcasted.
[0152] If the number of SSBs per PRACH occasion is less than or
equal to 1, preamble index=ra-PreambleStartIndex+n-1 are used for
nth On-Demand SI message for any SSB.
TABLE-US-00004 TABLE 4 Parameters (ASN.1) for RA Resources for SI
Request si-Request-Config SI-Request-Config OPTIONAL, --
Configuration for Msg1 based SI Request SI-Request-Config ::=
SEQUENCE { ra-PreambleStartIndex INTEGER (0..63), configurationType
ENUM {Common, Dedicated} OR dedicatedConfig ENUM {TRUE} OPTIONAL, }
}
[0153] UE selects a suitable SSB (above a threshold configured by
network in system information). UE then selects a preamble
corresponding to this SSB from the preambles corresponding to SI
message which UE wants to request. UE also selects a RACH occasion
corresponding to this SSB. UE then transmits Msg1 using selected
preamble and RACH occasion.
[0154] In an embodiment, ra-PreambleStartIndex is equal to
totalNumberOfRA-Preambles wherein totalNumberOfRA-Preambles is
signaled in system information (e.g. SIB1). The
totalNumberOfRA-Preambles indicates the number of RA preambles used
for normal random access procedure other than SI request. UE can
determine the list of ra-PreambleIndexes based on
ra-PreambleStartIndex, number of SSBs per RACH Occasion and
configuration type.
[0155] If configuration type is common, this means there is a
common configuration for all on Demand SI messages. This can be
indicated by signaling configuration type set to `common`.
Alternately, if dedicatedConfig is not included then configuration
type is common. In this case Msg1 (i.e. SI request) transmitted by
UE does not indicate request for a specific SI message and upon
reception of Msg1 network transmits all On-Demand SI messages. In
this case PRACH preambles from ra-PreambleStartIndex to
`ra-PreambleStartIndex+number of SSBs per RACH Occasion-1` are used
for SI request. The `ith` preamble in this list corresponds to ith
SSB amongst the SSBs associated with a RACH Occasion. In the
example of FIG. 13, 4 SSBs are mapped per PRACH occasion and there
are 16 SSBs. Network signals ra-PreambleStartIndex for SI request
in SI-Request-Resources. PRACH preambles from ra-PreambleStartIndex
to `ra-PreambleStartIndex+3` are used for this SI request.
[0156] If configuration type is dedicated, this means there a
dedicated configuration for each on Demand SI message. This can be
indicated by signaling configuration type set to `dedicated`.
Alternately, if dedicatedConfig is included then configuration type
is dedicated. In this case, if the number of SSBs per PRACH
occasion is larger than or equal to 1,
[0157] 1. The list of PRACH preambles from ra-PreambleStartIndex to
`ra-PreambleStartIndex+number of SSBs per RACH Occasion-1` are used
for first On-Demand SI message in schedulingInfoList. Mapping
between this list of preambles and SSBs is determined as explained
in embodiments 2 and 3; schedulingInfoList is a list of SI message
and indicates which SI message is On demand or broadcasted.
[0158] 2. The list of PRACH preambles from
`ra-PreambleStartIndex+number of SSBs per RACH Occasion` to
`ra-PreambleStartIndex+2*number of SSBs per RACH Occasion-1` are
used for second On-Demand SI message in schedulingInfoList. Mapping
between this list of preambles and SSBs is determined as explained
in embodiments 2 and 3; schedulingInfoList is a list of SI message
and indicates which SI message is On demand or broadcasted.
[0159] 3. The list of PRACH preambles from
`ra-PreambleStartIndex+2*number of SSBs per RACH Occasion` to
`ra-PreambleStartIndex+3*number of SSBs per RACH Occasion-1` are
used for third On-Demand SI message in schedulingInfoList. Mapping
between this list of preambles and SSBs is determined as explained
in embodiments 2 and 3; schedulingInfoList is a list of SI message
and indicates which SI message is On demand or broadcasted.
[0160] 4. The list of PRACH preambles from
`ra-PreambleStartIndex+(n-1)*number of SSBs per RACH Occasion` to
`ra-PreambleStartIndex+n*number of SSBs per RACH Occasion-1` are
used for nth On-Demand SI message in schedulingInfoList. Mapping
between this list of preambles and SSBs is determined as explained
in embodiments 2 and 3. schedulingInfoList is a list of SI message
and indicates which SI message is On demand or broadcasted. If the
number of SSBs per PRACH occasion is less than or equal to 1,
preamble index=ra-PreambleStartIndex+n-1 are used for nth On-Demand
SI message for any SSB.
TABLE-US-00005 TABLE 5 Parameters (ASN.1) for RA Resources for SI
Request si-Request-Config SI-Request-Config OPTIONAL, --
Configuration for Msg1 based SI Request SI-Request-Config ::=
SEQUENCE { configurationType ENUM {Common, Dedicated} OR
dedicatedConfig ENUM {TRUE} OPTIONAL, } }
[0161] UE selects a suitable SSB (above a threshold configured by
network in system information). UE then selects a preamble
corresponding to this SSB from the preambles corresponding to SI
message which UE wants to request. UE also selects a RACH occasion
corresponding to this SSB. UE then transmits Msg1 using selected
preamble and RACH occasion.
[0162] Determining the Discontinuous Reception (DRX) Cycle of
UE
[0163] In the existing system UE determines the DRX cycle (T) for
calculating its paging occasion (PO) as follows:
[0164] T1: UE specific DRX cycle value (configured by upper layer
signaling e.g. non access stratum (NAS)).
[0165] T2: Default DRX cycle value (broadcasted in system
information)
T=min(T1,T2)
[0166] In NR this may not work as T2 is multiple of remaining
minimum system information (RMSI) PDCCH monitoring occasions
interval. It is multiple of 20 ms or multiple of SS burst period
(i.e. 5, 10, 20, 40, 80, 160 ms). Since T1 is configured by upper
layer and is agnostic to RMSI PDCCH monitoring occasions
intervals.
[0167] FIG. 14 illustrates determining the DRX cycle of UE where
RMSI is frequency division multiplexed (FDMed) with SSB according
to an embodiment of the disclosure.
[0168] FIG. 15 illustrates determining the DRX cycle of UE where
RMSI is not FDMed with SSB according to an embodiment of the
disclosure.
[0169] In an embodiment, UE determines the DRX cycle (T) for
calculating its PO as follows:
[0170] X is the interval of PDCCH monitoring occasions for RMSI as
shown in FIGS. 14 and 15.
[0171] X=20 ms if RMSI multiplexing pattern is pattern 1;
[0172] X=SS burst set period if RMSI multiplexing pattern is 2 or
3. UE can determine the multiplexing pattern from the parameter
PDCCHConfigSIB1 in MIB.
T3=[T1/X]*(X)
T=min(T3,T2)
[0173] In an embodiment, UE determines the DRX cycle (T) for
calculating its PO as follows:
[0174] X is the interval of PDCCH monitoring occasions for RMSI as
shown in FIGS. 14 and 15.
[0175] X=20 ms if RMSI multiplexing pattern is pattern 1; X=SS
burst set period if RMSI multiplexing pattern is 2 or 3; UE can
determine the multiplexing pattern from the parameter
PDCCHConfigSIB1 in MIB.
T3=[T1 mod X]+T1
T=min(T3,T2)
[0176] Carrier Aggregation (CA) aspects for Bandwidth Part (BWP)
switching upon initiation of RA procedure
[0177] CA aspects are not considered yet for BWP switching upon
initiation of RA procedure.
[0178] For RA procedure initiated on secondary cell (SCell) (e.g.
SCell X), RAR is received on special cell (SpCell). The term SpCell
refers to the primary cell (PCell) of the master cell group (MCG)
or the primary secondary cell (PSCell) of the secondary cell group
(SCG). A SCell provides additional radio resources on top of
SpCell.
[0179] a) If RA resources are not configured for the active UL BWP
of SCell X, UE needs to switch the UL BWP to initial UL BWP of
SCell X. There is no need to switch the DL BWP of SCell X. In RA
procedure is initiated on SCell, RACH preamble is transmitted on
SCell but the RAR is received on SpCell. Switching the DL BWP of
SCell X will unnecessarily interrupt the DL transmissions on SCell
X. Since the contention free RA resource is used for RA procedure
initiated on SCell, gNB can identify the UE upon receiving the RACH
preamble and transmit the RAR on active DL BWP of SpCell. In case
of RA procedure initiated on SpCell, RAR is received on SpCell. For
RA procedure initiated on SpCell, contention based RA resource can
be used. gNB cannot identify the UE based on received RACH preamble
and hence cannot identify the active DL BWP of UE. So DL BWP
switching to an initial DL BWP is needed.
[0180] b) If RA resources are configured for the active UL BWP of
SCell X, the switching of DL BWP of SCell X based on linkage
between UL BWP and DL BWP of SCell X is not needed. In RA procedure
is initiated on SCell, RACH preamble is transmitted on SCell but
the RAR is received on SpPCell. Switching the DL BWP of SCell X
will unnecessarily interrupt the DL transmissions on SCell X. Since
the contention free RA resource is used for RA procedure initiated
on SCell, gNB can identify the UE upon receiving the RACH preamble
and transmit the RAR on active DL BWP of SpCell. For RA procedure
initiated on SpCell, contention based RA resource can be used. gNB
cannot identify the UE based on received RACH preamble and hence
cannot identify the active DL BWP of UE. So DL BWP switching based
on linkage is needed.
[0181] c) If common search space (CSS) is not configured in active
DL BWP of SpCell, UE cannot receive RAR, so UE should switch to
initial DL BWP of SpCell.
[0182] It is proposed that if RA procedure is initiated on SCell
and if CSS is not configured in active DL BWP of SpCell, UE switch
to initial DL BWP of SpCell. If RA resources are not configured in
active UL BWP, switching to initial DL BWP is applied for RA
procedure initiated on SpCell. If RA resources are configured in
active UL BWP, switching to DL BWP linked to UL BWP is applied for
RA procedure initiated on SpCell.
[0183] Upon initiation of the RA procedure on a Serving Cell, the
MAC entity shall for this Serving Cell:
TABLE-US-00006 1> if PRACH occasions are configured for the
active UL BWP: 2> If the Serving Cell is a SpCell: 3> if the
active DL BWP does not have the same bwp-Id as the active UL BWP:
4> switch the active DL BWP to the DL BWP with the same bwp- Id
as the active UL BWP; 1> else (i.e. PRACH occasions are not
configured for the active UL BWP): 2> switch the active UL BWP
to BWP indicated by initialUplinkBWP; 2> If the Serving Cell is
a SpCell: 3> switch the active DL BWP to BWP indicated by
initialDownlinkBWP; 1> If the Serving Cell is a SCell: 2> If
CSS is not configured for active DL BWP of SpCell: 3> switch the
active DL BWP of SpCell to BWP indicated by initialDownlinkBWP;
1> Perform the Random Access procedure on active DL BWP and UL
BWP of associated serving cell(s);
[0184] In an embodiment, upon initiation of RA procedure on a
serving cell, a UE identifies whether PRACH occasions are
configured for an active UL BWP of a serving cell. If PRACH
occasions are configured for the active UL BWP, and the Serving
Cell is a SpCell, and the active DL BWP does not have the same
bwp-Id, i.e., BWP identifier as the active UL BWP, the UE switches
the active DL BWP to the DL BWP with the same bwp-Id, i.e., BWP
identifier as the active UL BWP.
[0185] If PRACH occasions are not configured for the active UL BWP,
the UE switches the active UL BWP to an initial UL BWP
configuration for the serving cell. The initial UL BWP
configuration may be indicated by initialUplinkBWP in system
information. If PRACH occasions are not configured for the active
UL BWP and the Serving Cell is a SpCell, the UE also switches the
active DL BWP to an initial DL BWP configuration of the SpCell. The
initial DL BWP configuration may be indicated by initialDownlinkBWP
in system information.
[0186] The UE performs the RA procedure on the active DL BWP of the
SpCell and the active UL BWP of the serving cell.
Alternate Embodiment 1
[0187] During the Random Access procedure on a Serving Cell, the
MAC entity shall for this Serving Cell:
TABLE-US-00007 1> if PRACH occasions are not configured for the
active UL BWP: 2> switch the active UL BWP to BWP indicated by
initialUplinkBWP; 2> if the Random Access Preamble is selected
from contention based Random Access Preambles: 3> switch the
active DL BWP to BWP indicated by initialDownlinkBWP. 1> else:
2> if the Random Access Preamble is selected from contention
based Random Access Preambles: 3> if the active DL BWP does not
have the same bwp-Id as the active UL BWP: 4> switch the active
DL BWP to the DL BWP with the same bwp-Id as the active UL BWP.
1> perform the Random Access procedure on the active DL BWP of
SpCell and active UL BWP of this Serving Cell.
Alternate Embodiment 2
[0188] During the Random Access procedure on a Serving Cell, the
MAC entity shall for this Serving Cell:
TABLE-US-00008 1> if PRACH occasions are not configured for the
active UL BWP: 2> switch the active UL BWP to BWP indicated by
initialUplinkBWP; 2> if the Random Access Preamble is selected
from contention based Random Access Preambles: 3> switch the
active DL BWP to BWP indicated by initialDownlinkBWP; 2> else
(i.e. Random Access Preamble is selected from contention free
Random Access Preambles): 3> if the active DL BWP does not have
the same bwp-Id as the DL BWP active at the time this Random Access
procedure was initiated: 4> switch the active DL BWP to BWP with
the same bwp-Id as the DL BWP active at the time this Random Access
procedure was initiated; 1> else: 2> if the Random Access
Preamble is selected from contention based Random Access Preambles:
3> if the active DL BWP does not have the same bwp-Id as the
active UL BWP: 4> switch the active DL BWP to the DL BWP with
the same bwp-Id as the active UL BWP. 2> else: 3> if the
active DL BWP does not have the same bwp-Id as the DL BWP active at
the time this Random Access procedure was initiated: 4> switch
the active DL BWP to BWP with the same bwp-Id as the DL BWP active
at the time this Random Access procedure was initiated; 1>
perform the Random Access procedure on the active DL BWP of SpCell
and active UL BWP of this Serving Cell.
Alternate Embodiment 3
[0189] During the Random Access procedure on a Serving Cell, the
MAC entity shall for this Serving Cell:
TABLE-US-00009 1> if PRACH occasions are not configured for the
active UL BWP: 2> switch the active UL BWP to BWP indicated by
initialUplinkBWP; 2> if the Serving Cell is a SpCell: 3> if
the Random Access Preamble is selected from contention based Random
Access Preambles: 4> switch the active DL BWP to BWP indicated
by initialDownlinkBWP; 3> else (i.e. Random Access Preamble is
selected from contention free Random Access Preambles): 4> if
the active DL BWP does not have the same bwp-Id as the DL BWP
active at the time this Random Access procedure was initiated:
5> switch the active DL BWP to BWP with the same bwp-Id as the
DL BWP active at the time this Random Access procedure was
initiated; 1> else: 2> if the Serving Cell is a SpCell: 3>
if the Random Access Preamble is selected from contention based
Random Access Preambles: 4> if the active DL BWP does not have
the same bwp-Id as the active UL BWP: 5> switch the active DL
BWP to the DL BWP with the same bwp-Id as the active UL BWP. 3>
else: 4> if the active DL BWP does not have the same bwp-Id as
the DL BWP active at the time this Random Access procedure was
initiated: 5> switch the active DL BWP to BWP with the same
bwp-Id as the DL BWP active at the time this Random Access
procedure was initiated; 1> perform the Random Access procedure
on the active DL BWP of SpCell and active UL BWP of this Serving
Cell.
Alternate Embodiment 4
[0190] Upon initiation of the contention-based Random Access
procedure on a Serving Cell, the MAC entity shall for this Serving
Cell:
TABLE-US-00010 1> if PRACH occasions are not configured for the
active UL BWP: 2> switch the active UL BWP to BWP indicated by
initialUplinkBWP; 2> switch the active DL BWP to BWP indicated
by initialDownlinkBWP. 1> else: 2> if the active DL BWP does
not have the same bwp-Id as the active UL BWP: 3> switch the
active DL BWP to the DL BWP with the same bwp-Id as the active UL
BWP. 1> perform the Random Access procedure on the active DL BWP
of SpCell and active UL BWP of this Serving Cell.
[0191] FIG. 16 is a block diagram of a terminal according to an
embodiment of the disclosure.
[0192] Referring to FIG. 16, a terminal includes a transceiver
1610, a controller 1620 and a memory 1630. The controller 1620 may
refer to a circuitry, an ASIC, or at least one processor. The
transceiver 1610, the controller 1620, and the memory 1630 are
configured to perform the operations of the UE illustrated in the
drawings, e.g., FIGS. 2, 6, 8, 10 and 12, or described above.
Although the transceiver 1610, the controller 1620, and the memory
1630 are shown as separate entities, they may be realized as a
single entity like a single chip. Alternatively, the transceiver
1610, the controller 1620, and the memory 1630 may be electrically
connected to or coupled with each other.
[0193] The transceiver 1610 may transmit and receive signals to and
from other network entities, e.g., a base station.
[0194] The controller 1620 may control the UE to perform functions
according to one of the embodiments described above.
[0195] For example, the controller 1620 is configured to identify
whether PRACH occasions are configured for the active UL BWP. If
the PRACH occasions are not configured for the active UL BWP and
the serving cell is a SpCell, the controller 1620 is configured to
switch the active DL BWP to an initial DL BWP configuration
indicated by initialDonlinkBWP in system information. In addition,
the controller 1620 may be further configured to switch the active
UL BWP to an initial UL BWP configuration for the serving cell
indicated by initialUplinkBWP in system information if the PRACH
occasions are not configured for the active UL BWP. In addition,
the controller 1620 may be further configured to switch the active
DL BWP to a DL BWP with the same bwp-Id as the active UL BWP if the
PRACH occasions are configured for the active UL BWP and the
serving cell is the SpCell and the active DL BWP does not have a
same bwp-Id as the active UL BWP. The controller 1620 is configured
to perform the RA procedure on the active DL BWP of the SpCell and
the active UL BWP of the serving cell.
[0196] For example, the controller 1620 is configured to determine
whether a MAC SDU is associated with a CCCH or DCCH. If the MAC SDU
corresponds to a CCCH SDU, the controller 1620 is configured to
identify the size of the MAC SDU to determine a LCID field of MAC
subheader. The controller 1620 is configured to generate a MAC PDU
including the MAC subheader and the MAC SDU, and to control the
transceiver 1610 to transmit a Msg 3 associated with the generated
MAC PDU to the gNB. The size of the MAC SDU may be either 48 or 64
bits. If the size of the MAC SDU is 48 bits, the controller is
configured to set the LCID field to a first predetermined value.
Otherwise, the controller is configured to set the LCID field to a
second predetermined value different from the first predetermined
value.
[0197] For example, the controller 1620 is configured to control
the transceiver 1610 to receive information on resources for SI
request (i.e., SI-Request-Resources) from the base station. The
information on resources for SI request may include information on
a start index of at least one RA preamble for SI request (i.e.,
ra-PreambleStartIndex). The controller 1620 is configured to
control the transceiver to receive the information on resources for
the SI request in SIB1. The controller 1620 may be configured to
control the transceiver 1610 to receive information on a number of
SSBs per a PRACH occasion in the SIB 1. The controller 1620 is
configured to receive at least one SSB from the base station, and
select an SSB among the at least one SSB. The controller 1620 may
be configured to select an SSB above a threshold among the at least
one SSB. The controller 1620 may be configured to select any SSB if
none of the at least one SSB is above the threshold. The controller
1620 may be configured to determine a list of preambles for the SI
request based on the information on the start index and the
information on the number of SSBs per the PRACH occasion. The
controller 1620 is configured to determine a preamble for the SI
request corresponding to the selected SSB based on the information
on the start index. The controller 1620 is configured to control
the transceiver 1610 to transmit the determined preamble based on a
PRACH occasion corresponding to the selected SSB.
[0198] In an embodiment, the operations of the terminal may be
implemented using the memory 1630 storing corresponding program
codes. Specifically, the terminal may be equipped with the memory
1630 to store program codes implementing desired operations. To
perform the desired operations, the controller 1620 may read and
execute the program codes stored in the memory 1630 by using a
processor or a central processing unit (CPU).
[0199] FIG. 17 is a block diagram of a base station according to an
embodiment of the disclosure.
[0200] Referring to FIG. 17, a base station (BS) includes a
transceiver 1710, a controller 1720 and a memory 1730. The
controller 1720 may refer to a circuitry, an ASIC, or at least one
processor. The transceiver 1710, the controller 1720 and the memory
1730 are configured to perform the operations of the network (e.g.,
gNB) illustrated in the drawings, e.g., FIGS. 2, 7, 9, 11 and 12,
or described above. Although the transceiver 1710, the controller
1720, and the memory 1730 are shown as separate entities, they may
be realized as a single entity like a single chip. Alternatively,
the transceiver 1710, the controller 1720, and the memory 1730 may
be electrically connected to or coupled with each other.
[0201] The transceiver 1710 may transmit and receive signals to and
from other network entities, e.g., a terminal.
[0202] The controller 1720 may control the BS to perform functions
according to one of the embodiments described above.
[0203] For example, the controller 1720 is configured to control
the transceiver 1710 to receive a Msg3 associated with a MAC PDU
from a terminal. If the received MAC SDU is a CCCH SDU, the
controller is configured to identify the size of the MAC SDU based
on a LCID field of the MAC subheader.
[0204] In an embodiment, the operations of the BS may be
implemented using the memory 1730 storing corresponding program
codes. Specifically, the BS may be equipped with the memory 1730 to
store program codes implementing desired operations. To perform the
desired operations, the controller 1720 may read and execute the
program codes stored in the memory 1730 by using a processor or a
CPU.
[0205] A communication method and system for converging a fifth
generation (5G) communication system for supporting higher data
rates beyond a fourth generation (4G) system with a technology for
Internet of things (IoT) are provided. The communication method and
system may be applied to intelligent services based on the 5G
communication technology and the IoT-related technology, such as
smart home, smart building, smart city, smart car, connected car,
health care, digital education, smart retail, security and safety
services. A method of a terminal for performing a random access
procedure in a wireless communication system is provided. A method
by a terminal for transmitting a message 3 (Msg3) in a random
access procedure is provided.
[0206] While the disclosure has been shown and described with
reference to various embodiments thereof, it will be understood by
those skilled in the art that various changes in form and details
may be made therein without departing from the spirit and scope of
the disclosure as defined by the appended claims and their
equivalents.
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